This invention relates generally to an improved aerosol inhalation device, and more particularly to an aerosol enhancement device which is usable in combination with both a nebulizer and a metered dose inhaler.
Aerosol inhalation devices, for the purpose of delivering medication, entrained in an aerosol spray, to a patient using inhalation therapy, as an alternative to oral medications such as capsules or pills, or to injected medications, are well known in the art. For example, U.S. Pat. No. 4,210,155 to Grimes is representative of the prior art. In the Grimes patent there is disclosed a fixed volume mist accumulation chamber for use in combination with a nebulizer and a tee connection of an inhalation conduit for accumulating medicated mist and facilitating its delivery to a patient.
However, the Grimes device, as is typical for prior art devices, is plagued with problems typical of such devices. These problems include, for example, nonuniform concentrations of medication, resulting in difficulties in regulating patient dosage, and significant waste of medication. Additionally, the Grimes device is relatively complex, so that it is expensive to manufacture and difficult to use.
Many other such devices are available which do not include a mixing chamber. In other words, the nebulizer is attached directly to the aforementioned tee connection. Of course, such devices are even less suited to satisfactory regulation of the medication being delivered to the patient than the Grimes device, because there is substantially no ability to uniformly mix the medication with entrained fluid, such as air, before delivery to the mouthpiece on which the patient is inhaling.
In addition to nebulizers, metered dose inhalers (MDI) are also available for delivering a medicated aerosol to a patient. These MDI devices differ from nebulizers primarily in that a propellant is used to deliver the medication.
It would be advantageous to have an aerosol medication delivery device which included a mixing chamber between the medication delivery apparatus and the mouthpiece, wherein the medication could be uniformly mixed with entrained air in an improved manner over that achieved by the Grimes patent apparatus. It would also be beneficial for such a device to be simple to manufacture and assemble, and easy to use. Finally, if such a device could be made universally adaptable for use with any known nebulizer on the market, as well as with MDI's, this would be a great advance in the art.